Anorectal Manometry & Electromyography (EMG) Testing

Anorectal manometry is a test that evaluates patients with constipation or fecal incontinence. The test measures the pressures of the anal sphincter muscles, the sensation in the rectum, and the neural reflexes needed for normal bowel movements.

A complete anorectal manometry includes an electromyography (EMG). This is a test that evaluates patients with constipation or fecal incontinence. The test measures the anal sphincter muscle electrical activity, evaluating the nerve supply to the anal muscle. Anal sphincter EMG confirms the proper muscle contractions during squeeze and muscle relaxation during push. 

Anorectal manometry is safe and unlikely to cause pain. If allergic to latex, the test can be performed with a latex-free balloon. The test takes about 30 minutes. The patient lies on their left side. A small, flexible tube about the size of a thermometer, with a balloon at the end, is inserted into the rectum. The device is connected to a machine that measures pressure. The small balloon is inflated in the rectum to assess normal reflex pathways. The patient will be directed to squeeze, relax, and push at various times. The anal sphincter muscle pressures are measured during each of these maneuvers. 

Preparation for the procedure includes purchasing 2 Fleet enemas which as to be given 2 hours prior to leaving the house for the study. Nothing should be consumed during this time. Diabetics may need to adjust medications in preparation. Regular medications with small sips of water can be taken 2 hours prior to the study.

Normally, when stool enters the rectum, the anal sphincter muscle tightens to prevent passage of stool at an inconvenient time. The study measures the strength of the sphincter muscles and whether they relax as they should during passing a stool. The results provide helpful information when treating patients with fecal incontinence or severe constipation.